<![CDATA[Individual identification is very important in forensics. DNA can be obtained from all parts of the body with the same profile in everyone. Oral mucosal epithelium is one of the sources of DNA that is often used to examine individuals because it is taken using a harmless swab method. Smoke is one of the behaviors that are mostly done by young people or teenagers. Cigarette smoke affects the cells of the oral mucosa because it is a free radical. Free radicals are reactive oxygen compounds which are compounds with unpaired electrons. Deoxyribonucleic acid (DNA) is a nucleic acid polymer that is systematically arranged and is a carrier of genetic information that is passed on to offspring. This study aims to determine the quality and quantity of DNA in non-smoking and smoking students at the State University of Medan, Medan Tembung District, Medan City, North Sumatra Province. Samples were taken by swab method, namely mucosal epithelium from 60 probands consisting of 30 smoker proband and 30 non- smoking proband aged 18-22. The cheek in the probandus is swabbed from the back to the front in one direction. In this study, DNA extraction was carried out using a chelex solution which aims to separate DNA from protein, test the quantity of DNA with a spectrophotometer and test the quality of DNA with agarose gel. The results showed that the average DNA quantity in the oral mucosal samples was 1.96 ng/µL in the smokers proband and 6.92 ng/µL in the non-smoker proband and. The results of the quality test using electrophoresis on agarose gel showed that smoking students had thin bands of fluorescence and in some samples no bands of fluorescence at all. Meanwhile, in the probandus of non-smoker students, there were several samples that showed thin bands of luminescence and stains.]]>
